| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] [been] a key | 36 |
|
| 2 | have [been] a key | 36 |
|
| 3 | [vb -s] [been] a key | 22 |
|
| 4 | has [been] a key | 21 |
|
| 5 | [vb past] [been] a key | 8 |
|
| 6 | had [been] a key | 8 |
|
| 7 | [adv] [been] a key | 6 |
|
| 8 | [adv] [been] a key | 5 |
|
| 9 | [been] a key [noun sg] | 40 |
|
| 10 | [been] a key [noun] | 40 |
|
| 11 | [been] a key factor | 8 |
|
| 12 | [been] a key figure | 8 |
|
| 13 | [been] a key factor | 8 |
|
| 14 | [been] a key figure | 8 |
|
| 15 | [been] a key element | 5 |
|
| 16 | [been] a key element | 5 |
|
